Level indicator and recorder for molten glass



July 31, 1945. R. E. HOLDMAN 2,380,436

f LEVEL INDICATOR AND RECORDER FOR MOLTEN GLASS v Filed June'l9, 1944 '3Sheets-Sheet 2 L N @nu Y ATTORNEY `July 3l, 1945. vR E. HOLDMAN2,380,436

LEVEL `INDICATOR AND vRECORDER FOR MOLTE-.N GLASS Filed June 19, 1944 Q5 Sheets-'Sheet 3 Roe 5R7- E' l. z.: woeTH /OLDMA M INVENTOR ATTORNEYPatented July 3 1, 1945 'Ifhis invention relatestoimprovernents inapparatus for indicating Land recordingjvariations in the level of*molten glass in a melting tank.

`It `is one 'of the principal objects ofthis inven tiontoprovideapparatus of this character which y isof suchsensitivitythatitwill be actuatedby,

and caused `to record, variations inthe Lleveifof the molten glasswithi'nthet'ank down to `one onerhundredths (l/oqlof. an' inch, and isadaptable for adjustment"to1..ndicate and record levels i of otherfiuidsor molten material in tanks or vats.`

e Application June 19,1944, semi No. 541,066 e l a clams; @cm3-29o) iaeidble hose 8i connected with any convenient' sourceof supply. 'Iheconduit is open at its out f ermostgend-to admit water to the interiorof the shaftwhich drains out at the opposite end thereof through 'anoutlet` in connected with a drain' `alge hose I i.y Thusthe interiorofthe shaft re- .ceivers a constant now of cooling water sothat vtheportion Bof the shaft Aand the contact car- YI'he" foregoing andother'objects will appear as my invention isrnore fully hereinafterdescribed in the following specificationillustratedin the intheappendedclairns.. In thedrawin'gs':` e

Figure lis a side elevation of the device operatively connectedwithlatanlr which is fragmentarilyfshown. f Figure 2 is urelj"N e Figure3'isa detail view of "an arm, taken along the line 3;! `of Figure `21actuatedby the apparatus and adapted to "intermittently contact thesurfaceof the olten glassjwithin the` tank, to

accompanying drawings; and ijinally` pointed Vout an" enlarged top planvieww` of Figmake and break electrical circuit. l

Figure 4 is an enlarged `sectional front eleva` tionfof a portion ofFigure`2.

Figure `is an enlargedlongitudinal sectional view of the rotatable armdescribed in connection withFigure 3. l l

Figure 6"is a. fragmentary frontl elevation of Figure 4f showingcertaino'f the parts at one end oftheir range of opertion. i Figure '1Ais a diagramm electrical elements ofthe inventionoperativelyembracedwithinelectrical circuits. e .l

Referring now more particularly to the drawings: Y i f i 1N-Tm`Reference numeral ii indicatesa fragment of a glass-meltingltankfor vatwhosefront,rear, bottom end andtopfwalls areformed of refractorymaterial. To one wall of the tank I mount a platforni 2 in any approvedmanner as indicated at 3.* Upon the platform I mount avhollow shaft Iwhich' isrotatable within bearings 5 insulated aticlayout 4of certainried" thereby are enabled to `withstand the `high temperatures of theheat within' the tank. -The f shaft 4 is electrically connected by a,wire I2with a relayI switch generally indicated at I3 (see Figure'7).which'consists of a.J solenoid IIIl whose core at one end is notchedas at I5 for periodic-.en-

gagement with ahook i8 formed on lone leg of a bell-crank |1'pivotallymounted as at i8. AThe other leg I8 of the bell-crank is disposed in thepath of movement of an `arnrii carried by ka shaft 2i of a driven gear22 of a gear train to `bernore fully hereinafter described. The 'shaft l2i is connected to thev hollow shaft 4 and rotates the same through acoupling 23 made of insulating material to insulate the charged lshaft 4from e the shaft 2 I andits relatedv parts. l

The opposite end of the core of the solenoid I4 terminates ina switcharm made of insulating material end whose outermost .ends are providedwith metallic contacts 24 and 25 connected by wires 26 and 21respectively` with both sides of a powerline 28. Two pairs of Vcontacts29 and 3U are connected rby wires 3| and 32 respectively withvv anyapproved type motor indicated at 33' and reversible by change ofpolarity'. Thismo tor is operatively connected with the geartransmission 34 within which isincludedand finally `driven by the motor33 the previously mentioned gear 22. From the foregoing itwill beapparent that when themotor 33 isioperating in one direction, the hollowshaft 4 will vbe rotated to swing its portion 6 upwardly to removethecontact 'I out of contact with the molten glass as indicated at 35,and when the motor operates iii-an opposite direction it returns thecontact 1 of the shaft asat 5A from their support. The shaft extendsinto the tank through a suitable aperture 6B and its inner end i"sturned "at right anglesto itself as at 8 and provided withV enelectrical contact poses, "I provide the "interior of; the shaft with awatcrconduit [supplied withwaterthroulh V4 into contact with the glass.

The solenoid Il is connected to one side of the Y line 28 by a wire 38and to the opposite side of the line by the wire I21 `hollow shaft `4and its extension 6, the `contact 1 and the ground connection 31.

With the parts in the positions shown in Figure 7 the circuitis closedthrough the solenoid by'thecontacts 1, the molten glass 35, and theground connection 81 which` draws `1 preferably made ofplatinum. Forcoolingpurthe contacts 24 and'25 against the contacts 28 to close themotor circuit to cause it to operate in a direction-to lift the arm 6and contact 1 upwardly and out of contact with the glass 35. Thisrotation of the shaft 4 causes the arm 20 to strike the leg I9 ofthe-bell-crank il to disengage the hook portion I6 thereof from thenotch I in the core of the solenoid. When the core is thus released atension spring 38 pulls the contacts 24 and 25 away from the contacts 29and into engagement with the opposite contacts 3U which closes thecircuit to the motor through the wires 32 and y3i to cause the motor tooperate in an opposite direction which lowers the portion 6 of the shaft4 and the Contact 'l into electrical contact with the molten glass. Thusit will bc seen that the contact 1 intermittently and atperiodicintervals goes into and out of Contact with the level of theglass in the tank to close the circuits'as above outlined and t0 operatethe motor 33, first, in one direction and then in another. In the eventthat the level of the glass should accidentally rise to a dangerouslevel or to a point `where it would contact the'horizontal portion` ofthe shaft 4, I provide an automatic cut-out Vswitch consisting of a cam39 attached to and rotatable with the shaft 4,50 that if the portion 6of the shaft should swing upwardly to an excessive angle the lobe of thecam would press downwardly on a switch blade 40 through a piece Y ofinsulating material 40A to close a circuit 4| to energize a relay 42 toopen a main switch 43 in the power line 28. Opening of this switch ofcourse would render the entire system inoperative until propercorrection or adjustment of the glass feeding mechanism had beenattended to.

The indicating and recording portion Vof* the apparatus consists of ahousing 44 within which isrotatably mounted by means of bearings 45, ascrew shaft 46 which extendsroutwardly from one ond wall of the housingand engages by means of a coupling 41 with a shaft 48 which is drivenfirst in one direction and then in another by Vmeans of che vof thedriven gears 49 in the gear transmission 34 driven by the reversiblemotor 33. 'Fixedly mounted within the housing 44 are two horizontalparallel shafts 50 and 5i upon which is slidably mounted a block 52having an arm 53 extending outwardly therefrom and provided with aninwardlyrextending stylus 54 adapted to record on -a movable chart 55any movement of the block 52 to the right or left of its normal positionor its last position of reposo determined by the movement of certain ofits related parts hereinafter referred to. The block 52 is provided witha gear rack 56 engaged with and adapted to rotate a gear 51 secured to ashaft 58 which extends outwardly through the housing and which may serveas a power-takeoff for any desired purpose. Slidably mounted on thelower shaft 5| is a follower block 59 which is threadedly engaged withthe screw shaft 46 and movable therealong by rotation of the screwshaft. Y

Slidablymounted upon both` the shafts 50 and 5| is a yoke 60 whosefreedom of movement along said shafts is regulated by a spring actu- Yated drag 6i which may be regulated by a thumbnut 62 working against acompression spring 63 whose one end bears beneath the wing-nut and whoseopposite end bears against the top surface of the yoke to apply tensionto the collar 84 embracingA the shaftl 50, l'The more the thumb-nut isadvanced downwardly 4upon its boit I5 the more friction is createdbetween the collar 64 and the shaft 50.

The adjustable drag right leg of the yoke.

during the time the cam portion 6l of the ami 6B moves downwardly over apin 1D in the block 52 as the cam draws block 52 and its associatedindicating and/cr recording means toward the 'I'he yoke is also heldimmovable by the drag during the entire travel of block 59 from eitherleg of the yoke to the other.

'I'he resistance of the drag 6i is such that although it will render theyoke immovable as aforesaid, it will allow the yoke to readily yield tothe pushing action of the screw-driven block 59. To the yoke 60 Ipivotally mount an arm 66 whose outermost end is formed with a hookportion 6l and whose opposite or inner end is formed into a cam surface68 adapted to cooperate with and be actuated by a. cam surface 69 formedon the upper surface of the traveler block 59. i

Thus at the beginning of the cycle, as the traveler block 59, due to therotation of the screw shaft 4E, moves to the right as viewed in Figure 4out of contact with the left, leg of the yoke and toward contact withthe right leg thereof, the cam portion 69 will swing the cam portion 61of thca'rm 66 downwardly through a certain angle then back to itsoriginal position. The block 59 has now contacted the right hand leg ofthe yoke 6U, arm 66 being inthe same position as shown in Figure 4 (i.e. at the same position as at the beginning of the measuring cycle). Theyoke 60 and the block 59 now move to the right in xed relative position,until the moment that Contact 1 makes electrical-contact with thesurface of the molten glass. At 'this moment the motor 33 is reversedand therefore shaft 46 is likewise reversed. Thus as the traveler block.due to the rotation of the screw shaft 46, moves to the left as viewedin Figure 6 out of contact with the right leg of the yoke and towardcontact with the left leg thereof, the cam portion 69 of the block willswing the cam portion 61 of the arm 66 downwardly to slidably engagewith a pin TD extending outwardly from the block 52 of `the indicatingmechanism. If the level of the molten glass hasrnot changed since theprevious contact of the shaft 4 with the glass the right leg of the yokeSD will come into Contact .with the left-hand wall of the block 52 atthe moment. the cont-act with the glass is made which will enable thecam portion 61 of the arm B6 to freely settle down over the pin 'iii andto be lifted away from it without disturbing the setting of the block52. If, however, the level of the molten glass has changed and the yokedoes not quite contact the block 52,1;he cam portionl 6l of the arm 66will contact the pin l0 and upon its further downward movement will drawthe block to the left as viewed in Figure 6 so that the lefthand wall ofthe block 52 will be drawn up against the right leg of the yoke 60. Thismovement of the block of course moves indicating arm H to the left toindicate upon a scale 12 the amount cf such movement If an oppositechange in the level of the molten glass occurs, the right leg of theyoke 60 will contact the left wall of the block 52 and move it to theright which will cause the indicating arm ll to indicate this change inlevel in the opposite direction. In this case as in the case where thelevel of the molten glass has not changed. as the block 59 moves to theleft. as viewed in Figure 6. out of contact with the right leg o1' theyoke and toward contact with the left leg thereof. the cam portion 69will swim: the

-cam portion 61 of the-arm 66 downwardly to freely settle over the pin10 and to be lifted away t Y 1 2,380,436 from it without disturbmg thesetting that existed at the moment contact with the'glass surtothe .leftand at the moment the left-hand face' i otsaid' b1ockl59 moves intocontactwith the lefthand leglof yoke 60, the cam portion 61 of the armIll being in such a position that `it clears pin 10, the block and theyoke move to the left with relative positions as shown in Figure 4 untilthe arm` carried by shaft 2| strikes the leg `I9 i the cam` portion 61of the armBB at no time comes i into hooked engagement with the pin 10.The

` The movable chart 55 embraces and is `driven by ,a pair oi drums 13one of which is driven by a i synchronous motor 114. 'I'he chart `isprovided withtransverse graduations each indicating suc- )face was made.The block 5! continues to move t said block and movable" thereby atcertain limitsof` movement of the block, indicating and/or recordingmeans slidably mounted in the path of movement of the yoke to be movedthereby ingthe yoke and said indicating and/6r re-` 4l0 Tof the bellcrank l1 ,which causes the motor to A "operate in an oppositedirectionthereby com` i pleting the cycle. YIt is to be understoodthat t in onedirection, and means `for, interconnectcording means for movement in theopposite direction.

2.` In apparatus for indicating and/or recording `fluid `levels `in atank comprising means for intermittently contacting the fluid to closean electric circuit embracing and for operating a `reversible motor, thecombination of a traveler `cording means for movement in the oppositeblock movable in two directions by the operation of said motor, atraveling yoke embracing said block and movable thereby at certain linnits of movement of the block, indicating and/or recording means slidablymounted in the path of vmovement of the yoke to' be moved thereby `inone direction, and means for interconnectinggthe yoke and saidindicating and/or redirection, said means including a projection cessive`hours ofthe day `and night as shown, ,t

and the speed of travel ofthe chart is such that, it requires one hourto move the distance from one graduation to the next with respect tothestylus 5I. Thus I provide apermanent record of \chan`ges in the level ofthe glass over any desired period o! time.` i i t While I have shown aparticularform of embodiment oi my invention, I am` aware that manyminor` changes therein will readily` suggest themselves to othersskilledl inthe art without departing from the Spirit and scope o! theini`vention Having thus described my invention,

ywhat I claimas new land .desire to protectbyf Letters Patent is:

1. In apparatus for indicating fand/or recarriedV by the indicatingand/or recording means, and means pivotally mounted to the yoke, andy`movable into and `out of cammed engagement with said projection bymovement of said traveler block with respect to the yoke. i

3b In apparatus for indicating and/or recording uidlevels in a tankcomprising means for i "intermittently contacting the fluid to close anelectric circuit embracing and for operating a reversible motor, thecombination of a traveler `block movable in two directions by theoperation of said motor, a traveling yoke embracing said block andmovable thereby at certain limits `of movement of the block, indicatingand/or recording means movable by the yoke in one cording iiuid levelsin a tank comprising means for intermittently contacting the iluid toclosey an` electric circuit embracing and for operating a reversiblemotor, the combination of `a traveler block movable `in two directionsby the operation of saidimotor, a traveling yoke embracing direction,cam means actuated by the block for moving said indicating and/orrecording means t in `an opposite direction. and means carried by theyoke for stabilizing itself during the cam action in moving theindicating and/or recording means in said opposite direction.

,4 `ROBERT EILSWOR'I'E HOLDMN.

